Workable nickel and nickel alloy



lated elements Patented Sept. 16, 1941 WORKABLE. NICKEL AND NICKEL ALLOYLeonard Bessemer Pi'eil, Edgbaston, Birmingham, England, assignor to TheInternational Nickel Company, Inc., New of Delaware York, N. Y., acorporation No Drawing. Original application October 6,

1936, Serial No. 104,179. Divided and this application April 25, 1939,Serial No. 269,912. In Great Britain October 15, 1935 6 Claims.

The present invention relates to nickel and nickel alloy's havingimproved workability and products made therefrom including electricresistance units.

Nickel and its alloys have, in some cases, been somewhat diificult towork and under certain circumstances an alkaline earth metal has oftenbeen added to the molten materials. In order to obtain the full benefitsof the addition of the alkaline earth, it is desirable to add more ofthe alkaline earth metal, calcium' for example, than is consumed by thedesired chemical reactions. This results in a residue of calcium orother alkaline earth in the finished material (or a residue of someother element reduced from the furnace lining, slag, and so forth, bythe excess calcium, etc.), but it is important to control the amount ofalkaline earth metal that is left as the presence of more than a certainamount of calcium or other alkaline earth metal makes the materialunworkable.

I have made the surprising discovery that the necessity for strictcontrol of the amount of calcium or other alkaline earth metal can beavoided and, yet the materials can be rendered easily workable.

It is an object of the present invention to provide nickel and/or nickelalloys having improved workability.

It is another object of the present invention to provide means forobviating the need for extreme care in regulating the amount of alkalineearth metal added to nickel and/or nickel alloys. It is a further objectof the present invention to compensate for the excess of alkaline earthpresent in a nickel and/or nickel alloy material by the addition of aregulated, critical amount of another element usually considereddeleterious.

The present invention also contemplates the production of nickel alloysparticularly suitable for use as electrical resistance units.

Other objects and advantages will become apparent from the followingdescription.

In general, the present invention contemplatesmelting nickel and/ornickel alloying metals in the usual manner followed by the usualdeoxidizing, desulfurizing, etc. The deoxidizing, desulfurizing, etc.,may be carried out by the addition of calcium silicide or other alkalineearth metals or alkaline earth metal alloys, or by means of aluminum,cerium and re- (including thorium, hafnium,

metal is left in the finished material, and sim-' ilarly more than oneof the metals usually considered deleterious may be added.

-It is convenient to describe the nature of the present invention inconnection with calcium and arsenic, but it is to be understood thatthese may be replaced respectively by other alkaline earth metals andother elements of group V, i. e., phosphorus, antimony and bismuth.

The amount of calcium and the accompanying arsenic to be added to themelt varies according to the working conditions, i. e., the type offurnace, conditions of the lining, the speed of melting, the nature ofthe raw materials, and other similar factors, but in order to give anindication of the relative amounts of calcium and arsenic, it may bestated that when between about 0.05 and about 0.15% calcium is presentin the finished material that may advantageously be accompanied by about0.01 to about 0.05% arsenic. In general, it is preferred so to carry onthe process that small quantities of calciumand an element of group Vremain in the finished material because in this way,'it can be ensuredthat the beneficial effectsobtained by their addition to the moltenmaterial are produced to the full. The preferred ranges are as follows:

Per cent Per cent Element: by weight Element: by weight Calcium"- 0.01to 0.10 Phosphorus 0.01 to 0.06 Calcium--- 0.01 to 0.15 Arsenic 0.01 to0.2

Calcium--- 0.01 to 0.2 Antimony 0.01 to 0.25

In the case of bismuth, not more than about 0.075% should be added.

As is well known,.the calcium may be added as a metal or as an alloy orcompound, such as calcium silicide and the group V element may be addedin the elemental form or as an alloy or compound, such as, for example,nickel arsenide or calcium phosphide. The alloying process may becarried out in any suitable manner. Thus, a preliminary addition, ofvcalcium silicide may be made to the melt and any substantial excess ofcalcium removed by oxidation. A final calcium silicide addition may bemade just before casting. The less oxidizable of the group Velescandium, yttrium, and zirconium); and manme ts ay be a ded at a ystage n t e me ting process, or may be added in a suitable alloyed formwith the cold charge.

The additions may be made by plunging the elements or alloys to thebottom of the molten metal by any suitable means so as to improvethealloy-, ing process. The group V elements together with part or allthe'calcium, or other alkaline earth metal, may, however, be added tothe molten stream duringv the pouring of the metal. I

For the purpose of giving those skilled in the art a betterunderstanding of the present invention, the following examples are givenby way of illustration.

Example No. 1

a In the production of the well known, 80/20 nickel-chromium alloyaccording to the present invention, the following procedure may, forexample, be followed:

About 800 pounds of nickel are melted and subjected to deoxidation bythe addition of. about 0.25 to about 0.5% manganese and about 0.25%

silicon, about-200 pounds of chromium are added and when the mass ismolten, about 6 pounds of calcium silicide containing about 25% calciumare added. This is equivalent to adding-about 0.13% calcium to the melt.When suflicient time has been allowed for the desired reactions toproceed and the temperature of the metal hasbeen adjusted'to thatcorrect for casting, the metal is poured into a'ladle, and about 0.5 ofa pound of metallic arsenic is added thereto. About 1 pound of calciumsilicide is introduced into the ladle, and the metal is cast. These lastadditions represent about 0.045% and about 0.08%, respectively, of thetotal mass.

Example No. 2

nickel, the following example is given:

About 1000 pounds of commercial nickel are melted together with about0.25% manganese and about 0.1% silicon. When molten, the metal is pouredinto the ladle and during the pouring operation, an addition of about0.025% arsenic is made followed by about 0.05% calcium either in themetallic form or in the form of calcium silicide.

In the application of the present invention to the preparation ofiron-nickel alloys, the following example is presented for illustrativepurposes:

. Example No. 4

In the production of 50-50 nickel-iron alloy,

about 500 pounds of nickel and about 500 pounds of iron are meltedtogether with about 0.25%

manganese and about 0.1% silicon. ,When molten, the metal is poured intothe'ladle and during the pouring operationan addition of about 0.025%arsenic is made followed by the addition of about 0.05% calcium eitherin the metallic form or in the form of calcium silicide.

. made.

- electrical resistance alloys are also known as high particularadvantage to those nickel-chromium and nickel-chromium-iron alloys fromwhich, as a general rule, electrical resistance elements are As thoseskilled in the art know, such temperature resistance alloys, highresistance alloys, and the like, and include such alloys as'areavailable for use at elevated temperatures in excess of 500 C. Thoseskilled in the art have classified the nickel-containing alloys in, twogroups. For instance, Hunter and Jones in an article entitled "Someelectrical properties or high-resistance alloys, in the Proceedings ofthe American Society for Testing Materials, volume 24, 1924, part 11,page 401, referred to both the nickel-chromium alloys and thenickel-chromium-iron alloys. Hunter and Jones stated that binarynickel-chromium alloys containing up to 30% chromium had been made andthat the commercial alloys usually contained 15% to 20% chromium; Theauthors also stated that a well known nickel-chromium-iron alloycontained about 60 nickel, 26% iron, and 12% chromium, while anothercontained less iron and more chromium. It was also pointed out that manyof the alloys were worked under the Marsh patent. The Marsh UnitedStates Patent No. 811,859 of 1906 disclosed the use of nickel-chromiumalloys for electric resistance elements. Marsh's alloys contained over50% nickel or cobalt, or both, and less than 50% chromium, butpreferably contained less than 25% chromium and more than 75% nickel. Asexamples, the 90/10 and 85/15 nickel-chromium alloys were, cited. It waslater determined that the best alloy of the series was the 80/20nickel-chromium alloy. Handbook of Non-Ferrous Metallurgy, McGraw- Hill,1926, volume '2, page 1315, referred'to the nickel-chromium andnickel-chromium-iron alloys for heating elements and stated that thecommercial alloys contain 5% to 20% chromium,

5% to 40% iron and the balance nickel. The

Dempster United States Patent No. 901,428 of 1908 had disclosed the useof nickel-chromiumiron alloys for electric resistance elements. TheDempster alloys contained more than 10% and less than 50% iron, forexample, 20% iron. A

. loy containing 80% nickel and 20% chromium The present invention maybe applied with and the nickel-chromium-iron alloy containing 60%nickel, 25% iron and 12 to 15% chromium. Hunter stated that it wascommercially practicable to make binary nickel-chromium alloyscontaining up to 30% chromium. Hunter stated that the alloys may containcarbon, manganese,

silicon, aluminum, molybdenum, copper, etc., in'

small amounts, for example, 0.07% or 0.1% up to over 2%, and in someinstances, for example, molybdenum, as high as 10%. Briefly stated, the

nickel-containing alloys adapted for use as electrical heating elementsusually contain about 10% to about 30% chromium or more and the balancenickel or nickel and iron with or without some cobalt, the nickelcontent of the alloys generally exceeding about 50% nickel, i. e., thebalance is metal of the iron group of which at least 50% of the alloy ispreferably nickel. From their Liddells nature, these alloys give rise'tosubstantial difficulty during the wire producing processes on which thelife of the wire may depend. Accordingly, the invention includeselectrical resistance elements made from such alloys embracing smallquantities of one or more alkaline earth metals and one or more of thegroup V elements, i. e., phosphorus, arsenic, antimony, etc.

Thepresent application is a division of my copending 'patent applicationSerial No. 104,179, filed October 6, 1936, which, subsequent to thefiling of this application, matured into U. 5. Patent No. 2,159,048.

While the present invention has been described in connection withcertain preferred embodiments, it is to be understood thatvariations.and modifications may be made by those skilled in the art. Suchvariations and modifications are considered to be within the spirit andscope of the appended claims. i

It is to be understood that the term deoxidation, as used herein,includes such preliminary treatment as deoxidizing, desulfurizing, etc.

I claim:

1. As an article of manufacture, an electrical resistance element madeof an improved workable nickel alloy comprising about to about 30%chromium, about 0.01% to about 0.2% calcium, about 0.01% to about 0.25%or at least one senic andantimony, and the balance substantially allnickel.

3. As an article of manufacture, an electrical resistance element madeof an improved workbility comprising about 10% to about 30% chromium,about 5% to about iron, about 0.01% to about 0.2%, calcium, about 0.01%to about 0.25% of at least one of theelements of the group consisting ofphosphorus, arsenic and antimony, and the balance substantially allnickel.

5. A nickel-base alloy adapted for use-as an electrical heating elementcomprising about 10% to about 30% chromium, about 0.01% to about 0.2%alkaline earth metal, and at least one of the elements of the groupconsisting of phosphorus, arsenic and antimony within the range of about0.01% to about 0.06%, about 0.01% to about 0.2%, and about 0.01% toabout 0.25%, respectively, and characterized by high workabilitycompared to a similar alloy free from phosphorus, arsenic or antimony.

6. A nickel-base alloy containing from about 0.01% to about 0.2% ofalkaline earth metal, about 0.01% to about 0.25% of at least one elementfrom the group consisting of phosphorus, arsenic and antimony, andcharacterized by high workability compared to a similar alloy free fromphosphorus, arsenic or antimony.

' LEONARD BESSEIVIER. PFEIL,

